package c5;

public class Example9 {
    private static final  int TIMES = 100000;
    public static void main(String[] args) {
        Example9.testString();
        Example9.testStringBuffer();
        Example9.testStringBuffer();
    }
    public static void testString(){
        long startTime = System.currentTimeMillis();
        String str = "";
        for (int i = 0; i < TIMES; i++){
            str += "test";
        }
        long endTime = System.currentTimeMillis();
        System.out.println("String test usedtime:"
        + (endTime - startTime));
    }
    //StringBuffer时间效率测试（线程安全）
    public static void testStringBuffer(){
        long startTime = System.currentTimeMillis();
        StringBuffer str = new StringBuffer();
        for (int i = 0; i < TIMES; i++){
            str.append("test");
        }
        long endTime = System.currentTimeMillis();
        System.out.println("StringBuffer test usedtime: " + (endTime - startTime));
    }
    //StringBuilder 时间效率测试（非线程安全）
    public static void testStringBuilder(){
        long startTime = System.currentTimeMillis();
        StringBuilder str = new StringBuilder();
        for(int i = 0; i<TIMES;i++){
            str.append("test");
        }
        long endTime = System.currentTimeMillis();
        System.out.println("StringBuilder test usedtime: " + (endTime - startTime));
    }
}
